1. Field of the Invention
This invention relates generally to motor vehicles, and more particularly, to a system that reduces vehicular fuel consumption by providing an electronically-controlled, externally-charged, independent, auxiliary source of electrical power to the vehicle electrical system, thereby reducing engine loading due to the on-board vehicle generator.
2. Description of the Related Art
Conventional internal combustion or diesel powered vehicles provide electrical power for various electrically-powered devices, such as fans, pumps, lights, electronic controls, and other electrical loads. This power is typically generated by an engine-driven generator. Additionally, electrical energy is stored in a battery that is used to start the vehicle and to power the other electrical devices when the engine is not running. The battery is recharged when the engine is running, requiring additional power from the generator. This electrical power generation and usage proportionately reduces vehicle fuel economy by as much as 10%, depending on the vehicle operating condition and magnitude of the electrical loads.
Older vehicle power system designs supplied a fixed, temperature-dependent voltage from the generator, often resulting in battery overcharging, reduced battery life, and lower fuel economy. Newer designs endeavor to minimize unnecessary charging, and allow more power to be provided by the battery under certain conditions. These new systems regulate the generator voltage depending on the battery state-of-charge, current flow out of the battery, and vehicle electrical load condition, resulting in improved efficiency in the operation of the generator, and consequently improved fuel economy. However, notwithstanding such improvements, the electrical power is still ultimately supplied by the engine-driven generator, and the corresponding penalty in fuel economy remains significant.
The prior art has thrust at the problem of excessive fuel consumption resulting from vehicle generator loading by providing complex and expensive systems that require extensive modification to the vehicle. Some prior art approaches require a complex mechanical transmission system to be coupled to the shaft of the vehicle generator. Other known arrangements require modification of the generator windings or circuits that disable the vehicle generator under predetermined conditions.
It is, therefore, an object of this invention to provide an arrangement wherein the necessary electrical energy is provided to the vehicle without increase in the fuel consumption that would result from generating such electrical energy by the onboard generator.
It is another object of this invention to provide an external power source that easily can be recharged
It is also an object of this invention to provide an external power source that easily can be connected to a vehicle.
It is a further object of this invention to provide an arrangement that reduces vehicle generator loading without requiring modification to the vehicle electrical system, including the generator.